For those with access to IEEE standards (many universities do), the VHDL standards can be found using this site:
https://ieeexplore.ieee.org/xpl/opacstd.jsp
The VHDL standards are numbered 1076.x so narrow your search to include 1076. This will get you access to the definitive source.
By Nicholas Outram
Dr. Nicholas Outram is an Associate Professor in Computing and Electronics in the School of Computing and Mathematics, Plymouth University, UK. He specialises in iOS development, Biomedical Signal Processing, Embedded Software Development and VHDL. Dr. Outram has developed and heads-up an intensive fast-track iOS development course for students, academics and engineers both in Plymouth and overseas. He also develops iOS applications for research and teaching. Dr. Outram has a Ph.D. in Biomedical Signal Processing and Artificial
Intelligence and a first class honours degree in Electrical & Electronic Engineering. Before returning to academia, he worked for 5 years in industry as a DSP engineer and research engineer.
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